World Climatic Regions

Climate is a measure of the average pattern of variation in temperature, humidity, atmospheric pressure, wind, precipitation, atmospheric particle count, and other meteorological variables in a given region over long periods of time. Any independent study of each of these elements does not present any comprehensive view of climate. On the basis of these elements, there could be thousands of types of climates in the world.

Weather

Weather refers to the conditions in the air over a short period in a specific place. It involves things like how hot or cold it is, how much humidity is in the air, if it’s raining, the air pressure, wind, and cloud cover.

Weather is different from climate. Weather is about what’s happening now, while climate is a summary of the typical weather patterns in a place over a much longer time, like 30 years.

Most weather events occur in the troposphere, which is the lower part of the Earth’s atmosphere. It goes from the surface up to about 4-5 miles at the poles and 11 miles at the equator.

The troposphere is essential for weather because nearly all clouds and precipitation happen here. Things like jet streams and upper-air waves higher up also influence the pressure patterns, creating highs and lows that impact surface weather.

Geographic features like mountains and large bodies of water (lakes, oceans) can affect weather. For example, mountains can block or redirect winds, and water bodies can moderate temperatures.

Recent studies show that anomalies in ocean-surface temperatures can cause unusual weather patterns in different seasons and places. One well-known example is El Niño/Southern Oscillation (ENSO), where the interaction between the ocean and atmosphere influences global weather conditions.

Climate

Climate, conditions of the atmosphere at a particular location over a long period of time; it is the long-term summation of the atmospheric elements (and their variations) that, over short time periods, constitute weather.

These elements are solar radiation, temperature, humidity, precipitation (type, frequency, and amount), atmospheric pressure, and wind (speed and direction).

About World Climatic Regions

Hot, Wet Equatorial Climate

Geographical Distribution: The equatorial region extends approximately 50 degrees north to 100 degrees south of the equator, creating a broad belt around the Earth. Moving away from this zone results in a transition to a monsoon-type climate, with the characteristic of hot and wet weather. Interestingly, there are exceptions, such as cooler places like Malaysia’s Cameron Highlands, thanks to their higher altitude.

Climate: Imagine a place where the temperature remains almost constant throughout the year, hovering around a comfortable 24 to 27ºC. In this equatorial paradise, winter is nonexistent, and the temperature doesn’t fluctuate much on a daily or yearly basis. Rainfall is abundant, ranging from 60 to 100 inches, evenly spread throughout the months. Notably, the region experiences double rainfall peaks during the equinoxes, adding a unique touch to its climate.

Natural Vegetation: A Lush Landscape filled with tropical rainforests – the equatorial trademark. The Amazon tropical rainforest, locally known as Selvas, is a dense tapestry of evergreen trees like mahogany, ebony, greenheart, and cabinet wood. It’s a haven for biodiversity with lianas, epiphytic plants, and even parasitic plants thriving. Unlike other regions, finding a concentration of single-species trees here is a rare sight.

Economy: Step into the equatorial regions, and you’ll likely find sparsely populated areas. In the heart of the forests, early communities lead lives as hunters and collectors, while more advanced societies engage in shifting cultivation. Plantation crops, including natural rubber and cocoa, add economic diversity to these regions, creating a unique blend of traditional practices and emerging industries.

Savanna or Sudan Climate (or Tropical Wet and Dry Climate)

Savanna or Sudan climate is like the middle ground between lush equatorial forests and scorching trade wind deserts. Picture it dancing between the Tropic of Cancer and the Tropic of Capricorn, mainly showing off its moves in Sudan, where the dry and wet seasons really know how to strut their stuff. This climate is the life of the party, spreading its good vibes over vast areas in Africa (shoutout to Kenya, Nigeria, and Gambia), Australia, South America (Brazilian highlands represent!), and even making a cameo in India.

Geographical Distribution: The Savanna climate is found in tropical regions on both sides of the equator, with a notable presence in Sudan. It experiences distinct wet and dry seasons. In the northern hemisphere, this climate is observed in Africa (African Sudan, East Africa) and South America (Llanos grasslands of the Orinoco river basin).In the southern hemisphere, it spans South America (Campos grasslands of the Brazilian Highlands) and Australia (specifically in Northern Australia, south of its monsoon strip).

Temperature: Monthly temperatures in the Savanna range from 20 to 32 degrees Celsius in lowlands, increasing as one moves away from the equator. The annual average temperature hovers around 18 degrees Celsius. The highest temperatures occur just before the rainy season, around April in the northern hemisphere and October in the southern hemisphere. During the rainy season, overcast skies lead to a drop in temperatures, while noon temperatures can surpass 37 degrees Celsius in the hot season. Clear skies contribute to rapid nighttime radiation loss, with temperatures dropping below 10 degrees Celsius. Night frost is common during this season, highlighting the extreme diurnal temperature range.

Precipitation: The region experiences a hot, rainy season and a cool, dry season. In the northern hemisphere, the hot and wet season occurs from May to September, while in the southern hemisphere, it takes place from October to March. Rainfall and the length of the rainy season decrease as one moves away from the equator towards desert fringes.

Winds: Trade winds, flowing from east to west, are predominant in the region, bringing rainfall to coastal areas. In West Africa, off-shore trade winds, known as Harmattan, bring dry and dusty winds from the Sahara, providing relief from the damp air but adversely affecting crops. Trade winds contribute to distinct dry and wet seasons. Onshore winds in summer bring moisture-laden winds, while off-shore winds in winter keep the weather dry.

Vegetation: The typical vegetation includes tall grass with short trees, often referred to as ‘bush-veld’ or ‘parkland.’ Deciduous trees, like Acacia, shed their leaves during the dry season to prevent transpiration losses. Grass is tall and coarse, with elephant grass reaching heights of up to 15 feet. As one moves towards the desert, grasslands transition into thorny scrubs.

Wildlife: The Savanna is home to some of the largest terrestrial animals, with herbivores like zebra, giraffe, and elephants, and carnivores like lion, hyena, and leopard. Along rivers and marshy lands, reptiles such as crocodiles, monitors, and giant lizards, as well as rhinos and hippos, are found.

Economy: Nomadic pastoralists, like the Masai in Kenya and Tanzania, depend on animal stock for survival. Settled agriculture is practiced by group like the Hausa, who also domesticate animals for crop cultivation. Plantation agriculture is developed in various regions, cultivating crops such as cotton, sugarcane, oil palm, and tropical fruits. Some areas leverage modern science and technology to become leading exporters of meat and dairy products, despite challenges like frequent droughts and poor soil quality. For example, Queensland in Australia has excelled in this regard.

Tropical Monsoon Climate

The monsoon climate, also known as the tropical monsoon climate, is like nature’s mood swings in the region between the Tropic of Cancer and the Tropic of Capricorn. It’s hot and humid all year round because the sun decides to park itself right overhead, creating a perpetual sauna vibe. Monsoons are like seasonal dance partners for the land and seas, doing a back-and-forth routine. There’s this cool twist where the winds decide to switch directions, giving us a taste of changing temperatures and rainfall. So, we’ve got our three main acts: summer, winter, and rainy seasons, each with its own distinct flavor in this climatic rollercoaster.

Geographical Range: This climate is basically the VIP guest list limited to the 5-30 degrees latitudes on both sides of the equator. Think of it as the exclusive club that includes the Indian subcontinent, Indo-China (countries like Laos, Vietnam, Cambodia), Thailand, southern China, and the northern part of Australia.

Winds: During summers, Asia gets its groove on with low-pressure vibes, while down under in Australia, high-pressure takes the stage. Winds twirl from Australia towards Java, creating the famous South-West monsoon winds. Come winter, the wind playlist flips.

Temperature: The average monthly temperature hovers above 18 degrees Celsius, but when summer hits, it can crank up to a scorching 45 degrees Celsius. Winters, on the other hand, keep it mild, ranging from 15 to 30 degrees Celsius. It’s like nature’s own temperature-controlled dance floor.

Precipitation: It’s the ultimate rainfall bash, with an annual average of 200-250 cm. Some regions go all out with a staggering 350 cm. Places like Mawsynram and Cherrapunji in India are the true rain champions, receiving over 1000 cm, thanks to the wind playing matchmaker with the hills.

Seasonal: No dull moments here. Unlike the monotonous beat of equatorial climates, this one has distinct seasons. Summer is a hot, dry fiesta from March to mid-June. Rainy season steals the show from mid-June to September, with over 70 percent of the annual rainfall making a grand entrance. Cold dry season, from October to February, bids adieu with a graceful retreat of the monsoon winds.

Hot Dry Season: March to mid-June, where temperatures can hit a sweltering 44 degrees Celsius in some areas. Rainfall takes a vacation, with occasional thunderstorms.
Rainy Season: Mid-June to September, when monsoons decide to throw a massive water party. Over 70 percent of the yearly rainfall gets an invitation.
Cold Dry Season: October to February, as the monsoons make a graceful exit. Winds change direction, and some regions get a sprinkle of rain, essential for winter crops.

Monsoon Forests: Enter the enchanting world of monsoon forests – the Tropical Monsoon Forests. These deciduous beauties shed their leaves strategically during the dry season to conserve energy. They come in two flavors: moist deciduous and dry deciduous, adding variety to the green palette.

Economic: In these bustling regions, high population density is the norm. Picture subsistence agriculture as the main act, with a side of shifting cultivation and plantation agriculture. Cereals like rice, wheat, and maize take the spotlight in north India, while the highlands of the south and east show off with tea, coffee, rubber, and bananas. Lumbering adds the finishing touch, with hardwoods like Teak, Sal, Acacia, and Bamboo taking center stage. It’s a harmonious blend of nature and economy.

Desert Climate

Desert regions are characterized by very little rainfall and scanty vegetation. The length of the growing period is limited to a small rainy season. The landscape of the region is devoid of trees and animals due to the lack of moisture and food. They can be of two types: hot deserts – like Saharan desert, mid-latitude deserts – like Gobi desert.

Hot Deserts – Distribution: Hot deserts are mainly located on the western edges of continents, roughly between 15 to 30 degrees north and south of the equator. Some well-known hot deserts include the Sahara, Great Australian Desert, Arabian Desert, Kalahari Desert, Thar Desert, Mohave, Sonoran, Californian, Mexican Deserts in North America, and the Atacama Desert in South America

Temperature in Hot Deserts: Hot deserts are incredibly hot throughout the year, with no distinct cold season. Summer temperatures consistently stay above 30 degrees Celsius. The highest recorded temperature was a scorching 57 degrees Celsius in Libya in 1922.Factors contributing to these high temperatures include clear skies, strong sunlight, dry air, and rapid evaporation. Coastal areas are somewhat cooler due to the influence of seas and cold currents.

Temperature Fluctuations: Interior regions of hot deserts experience extreme temperature variations between hot summers and cold winters. The diurnal temperature range (difference between day and night temperatures) is significant, ranging from 14 to 25 degrees Celsius. Nighttime temperatures can drop sharply due to heat loss through radiation, especially in the absence of clouds.

Precipitation in Hot Deserts: Average annual precipitation in hot deserts is minimal, usually not exceeding 25 cm. These deserts fall within the Sub-Tropical High-Pressure Belts, where descending air masses hinder cloud formation. Prevailing Trade Winds blow off-shore, keeping moisture-laden winds from reaching the deserts. Westerlies, which could bring moisture, do not blow over these regions. Relative humidity decreases from 60 percent in coastal areas to less than 30 percent in interiors, contributing to permanent drought conditions. Cold currents along the west coasts of continents dry the air further, preventing significant rainfall. However, occasional intense thunderstorms may cause short-lived downpours and landslides. The Atacama Desert holds the title of the world’s driest region, receiving less than 2 cm of annual precipitation.

Mid-Latitude Deserts: Mid-latitude deserts, like the Gobi, Turkestan, Patagonian, and Ladakh deserts, are usually located on plateaus within continental interiors

Climate of Mid-Latitude Deserts: These deserts share similarities with hot deserts due to their distant location from coasts and the barrier of high mountains, hindering moisture-laden winds. Average annual precipitation remains below 25 cm. While depression may bring occasional light winter rainfall in Asia, convectional rainfall is possible in summers. Extreme temperatures result from continentality, with winters experiencing freezing temperatures and strong cold winds. Thawing ice in summers can lead to occasional floods.

Vegetation in Mid-Latitude Deserts: Despite appearing dormant, deserts exhibit various vegetation like xerophytic scrub, including bulbous cacti, wiry grasses, thorny bushes, and dwarf acacia. Regions with abundant groundwater may have clusters of date palms. Specialized vegetation adapts to intense aridity, featuring long roots, few or no leaves, and protective seed mechanisms.

Soil Characteristics: Soils lack humus due to moisture absence, slowing down organic matter decomposition. Shrub vegetation develops long roots to search for groundwater, with foliage designed to minimize water loss through transpiration.

Life in the Deserts: Diverse human settlements thrive despite challenging conditions. Early hunters and gatherers, such as the Bushmen in the Kalahari and Bindibu in Australia, live without cultivating crops or domesticating animals. Nomadic herdsmen like the Bedouins in Arabia and Tuaregs in the Sahara follow a livestock economy, wandering in search of water and pastures. Settled cultivators, found near rivers like the Nile, Indus, Colorado, and Tigris-Euphrates, cultivate crops such as wheat, barley, sugarcane, fruits, and vegetables. Mining settlers, engaged in activities like gold mining in Australia, diamond mining in Kalahari, copper mining in Chile, silver mining in Mexico, and oil extraction in Persian Gulf countries, have established significant communities.

Steppe Climate

The term steppe refers to a region which is a semi-desert with a grassland or shrub vegetation. Steppes are intermediate regions, not receiving enough rainfall to support a forest but are also not as dry as a desert. Steppe Climatic region is also known as Temperate Grasslands. These grasslands are some of the most developed agricultural fields and are termed as grain baskets. Livestock ranching is another major activity carried out in these areas due to the availability of natural grasses.

Geography: Steppes are vast grasslands located in continental interiors, primarily in temperate latitudes, influenced by Westerly winds. They span over 2000 miles from the Black Sea to the Altai mountains, characterized by a lack of trees. Known by different names globally, including Prairies in North America, Pustaz in Hungary, Pampas in Argentina, Velds (High Veld) in South Africa, Downs in Australia, and Canterbury in New Zealand.

Rainfall: Annual rainfall varies from 25 to 75 cm, with the highest precipitation in spring or before summer, especially in June and July. Winters experience occasional snowfall due to Westerlies, with an average of 25 cm.

Temperature: Steppes face extreme temperatures due to continentality. Summers are warm (18-20°C), and winters are cold with occasional snowfall. Northern hemisphere steppes have a high annual temperature range, while southern hemisphere ones have a more moderate climate.

Winds: Prevailing Westerlies bring winter precipitation. Local winds like Mistral, Loo, Sirocco, Foehn, and Chinook impact the weather. Chinook, a hot wind in North American Prairies, benefits local agriculture by melting snow, allowing animals to graze.

Vegetation: Temperate grasslands, unlike tropical savannas, are practically treeless with short, nutritious grass. Prairie soils are rich black earth. Grass is lean and scattered, ideal for large-scale livestock rearing or ranching. Trees are planted around croplands for wind protection.

Economic: Prairies are like the farmers’ paradise, growing wheat and maize on a massive scale. Vast lands make mechanized farming a breeze, and these areas are top producers of dairy and other animal products. Steppes might not have the most diverse animal crew, but they’re big on horses and extensive cattle and sheep ranching. Nomadic herding is a thing, especially in Eurasia, where the weather makes settled farming a bit tricky. Kazakhs and Kirghiz in Eurasia keep the nomadic vibes alive, herding their way through the vast steppes. Collective farming, introduced by Russia, gives a nod to teamwork where water is more generous.

Prairies are the wheat and livestock champs.
Velds rock sheep and cattle along with maize.
Pustaz is where wheat and beet sugar take the stage.
Pampas is the wheat hub with a side hustle of exporting dairy and beef goodies.
Downs and Canterbury are wooly wonders, producing Merino sheep wool and dishing out dairy delights.